Why Are Eukaryotic MRNAs Not Polycistronic, Unlike Some Bacterial Transcripts

question 46

Multiple Choice

Why are eukaryotic mRNAs not polycistronic, unlike some bacterial transcripts?

• A) The eukaryotic ribosome must bind to the 5' end of the mRNA and scan, while the bacterial ribosome can bind to a Shine- Delgarno sequence anywhere in the mRNA.
• B) Bacteria couple their translation with transcription, while eukaryotes do not.
• C) Eukaryote's genetic code is non- overlapping, and so coding sequences cannot overlap on the same mRNA.
• D) Eukaryotes have more complex translational machinery than bacteria that is also less efficient in initiating translation.
• E) Eukaryotic mRNAs are generally shorter than bacteria mRNAs, and so do not contain sufficient information to encode additional polypeptides.

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Definitions:

Founder Effects

A genetic phenomenon that occurs when a new population is established by a very small number of individuals from a larger population, leading to a reduction in genetic variation and a potentially different genetic structure compared to the original population.

Allele Frequencies

The proportion or prevalence of different alleles (versions of a gene) in a particular population, which can change over time due to evolutionary pressures.

Blood Stains

Evidence in the form of blood marks left on surfaces, which can be analyzed in forensic science to help reconstruct events at a crime scene.

Cut Marks

Physical evidence on bones that indicates the use of tools by humans or other species to process carcasses.